设函数y=sin(x2-1),则dy等于().A.cos(x2-1)dxB.-cos(x2-1)dxC.2xcos(x2-1)dxD.-2xcos(x2-1)dx
设函数y=sin(x2-1),则dy等于().
A.cos(x2-1)dx
B.-cos(x2-1)dx
C.2xcos(x2-1)dx
D.-2xcos(x2-1)dx
B.-cos(x2-1)dx
C.2xcos(x2-1)dx
D.-2xcos(x2-1)dx
参考解析
解析:dy=y'dx=cos(x2-1)(x2-1)'dx=2xcos(x2-1)dx
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